Relay



ocr. 24, 1944.

RELAY W. W. ElTEL ETAL Filed Feb. 1l, 1942 muuu Hl, 22 ZZ" /4 23 INVENTORS WILLIAM W E/TEL THEIR ATTORNEY Patented Oer. 24, 1944 RELAY william w. Enel and Jack A. Mecuu'eugh, san Bruno, Calif., assignors to Eitel-McCullough, Inc., San Bruno, Calif., a corporation of California Appueauon February 11, 1942, lsei-nil No. 430,388

' 'z claims. (c1. 20o-87) Our invention relates to a vacuum relay in which the relay parts are enclosed within an evacuated envelope.

It is among the objects of our invention to provide an improved construction and arrangement of relay parts within the envelope.

Another object is to provide an improved armature and mounting therefor.

A further object is to provide an improvedv magnetizable core within the envelope for controlling the amature.

' The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following descrip- -tion of our invention. It is to be understood that we do not limit ourselves to this disclosure of species of our invention, as we may adopt variant embodiments thereof within the scope' of the claims.

Referring to the drawing:

Figure 1 is a longitudinal vertical sectional View of a relay embodying the improvements of our invention, taken in a plane indicated by line I-I of Figure 2; and

Figure 2 is a transverse vertical sectional view of the same, taken in a plane indicated by line 2 2 or Figure 1.

Figure 3 is an exploded view of the armature.

In terms of broad inclusion, our improved relay comprises an envelope having a pair of aligned branches and a third branch angularly disposed thereto,and a three-part relay mechanism arranged -in the envelope. Each part of the mechanism terminates in a-lead, one of the leads being sealed in each of the envelope branches."

One of the relay parts includes a core and another part includes an armature. Means external the envelope are also provided for magnetizing the core to control the armature. Improvements.

are further provided in the construction and arrangement of the core and armature.

In greater detail, and referring to the drawing, our vacuum relay comprises an evacuated envelope of suitable material, such as glass, having coaxial tubular branches 2 and 3 and a third tubular branch 4 disposed at substantially right angles thereto. Branches 2 and 4 are of substantially equal length, and branch 3 is quite short compared to the others, thus providing an L-shaped body. The envelope is evacuated through a suitable tubulation which is sealed off at point 6.

The relay mechanism comprises three parts, each terminating in a lead sealed in a separate branch of the envelope. A pair of these leads 'I and 8 are aligned and project into the envelope Y through the ends of branches 2' and 3 respectively. 'Ihey are sealed to the glass by seals 9 and I I formed at the ends of the tubular branches. .The inner ends of these leads provide contact points and `are spaced apart and lie on opposite sides of the axis of branch 4. The third lead I2 projects into the envelope from the end of branch I, through a seal I3. These various leads are of a suitable metal, preferably tungsten.

The armature part of the relay mechanism is connected to lead I2, and comprises a pair of soft iron plates I4 and IIiv disposed between the aligned leads. Armature plate I4 is longer than the other and is secured to a pair of resilient arms I'I of say tungsten. The lower ends of arms II are held by a suitable bracket I8 formed to embrace the arms and lead I2; and the upper ends of the arms are welded to a strap I9 which in turn is welded to plate I 4. A pair of tungsten contacts 2I are arranged in apertures 22 in armature plates I4 and I6 for contacting the ends of aligned leads l and 8. It is diiiicult to weld tung` sten directly to iron, so We weld the contacts to opposite faces of a-thin sheet 23 of nickel, which in turn'is welded between the iron plates of the elongated cylinder 24 of magnetizable materiel' preferably soft iron, disposed about lead 'l in branch 2 of the envelope, with an end of the coreV terminating close to the inner end of lead 'I near the armature plate I4. This core is magnetized by an external coil 25 disposed about envelope branch 2, so as to control the armature. Thus, when coil 25 is energized, the armature is attracted by themagnetized core to break contact with lead 8 and establish contact with lead 1. When the coil is deenergized the resiliency of arms Il causes the armature to reengage lead 3.

As best shown in Figure 1, core 2d is connected to lead 'I at the core end remote from seal S, the remaining portions of Vthe core being spaced from the lead by a bore v2t of larger diameter than the lead and extending into the core from the end nearest seal 9. Connection between the core and lead is'preferably .made by press tting the lead in a hole at the end of the core, allowing the lead to project a slight distance beyond the end face of the core for engaging the amature contact.

By thefabove described construction the core is spaced from the lead for the major portion of the core length, and vheat generated in the core must travel back along the length of lead 'I before reaching seal 9 by conduction. This tends to thermally isolate the seal from the core, and prevents the glass at the seal from cracking.

Another important feature isthat the hollow core construction facilitatesoutgassing the metal during evacuation of the envelope. Outgassing metal parts in a vacuum device is always a serious problem, and is particularly diicult of accomplishment when a heavy piece of metal, such as iron core 24, is present.v Our improved core, with its bore 26 communicating with the envelope, exposes the interior of the iron mass so that more thorough outgassing of the metal is assured.

Any suitable means, such as a high frequency coil disposed about the envelope, may be employed to heat the internal parts of the relay for outgassing purposes during the exhaust process. v

\ We claim:

1. An electrical contactor device comprising an envelope having a pair of coaxial branches and a third branch angularly disposed thereto, a pair of aligned leads sealed in the coaxial branches, a third lead sealed in the third branch,

an armature supported on the inner end of the` third lead and engageable with either one or the other or the aligned leads, a core carried by one of the aligned leads for controlling the armature, and resilient means for normally l holding the armature engaged with one of th'. aligned leads.

3. An electrical contactar device comprising an envelope having a pair of angularly disposer branches, leads sealed in said branches, an ai mature mounted on one and engageable with thy 'other lead, a core in the branch containing sait other lead, and a coil disposed about the last mentioned branch for magnetizing the core.

4. An electrical contactor device comprising an envelopel having a pair of coaxial branches and a third branch angularly disposed thereto, a pair of aligned leads sealed in the rcoaxial branches, a third lead sealed in the third branch, an armature mounted on the third lead and engageable with either one or the other 'of the aligned leads, and a core carried by one of the aligned leads for controlling the amature, said core being supported on the lead at a point remote from the end oi' the branch in which the last mentioned lead is sealed.

5. An electrical contacter device comprising an envelope; a pair of leads projecting into the envelope; a magnetizable core carried by one of the leads; and an armature disposed between the leads comprising a pair of apertured plates, a sheet interposed between the plates, and a pair of contacts secured to opposite sides of the sheet and lying in the plate apertures. f Y

6. An electrical contactor device comprising an evacuated envelope, a lead sealed 'in the envelope, another lead sealed in the envelope, an

, armature resiliently mounted on said other lead and engageable with the ilrst mentioned lead, and a magnetizable core carried by the rst mentioned lead.

7. An electrical contactor device comprising an evacuated envelope, a pair of leads sealed .in the envelope, a third lead sealed in the envelope, an armature resiliently mounted on the third lead and engageable with either one or the other of said pair of leads, and a'magnetizable core carried by one of said pair of leads.

WILLIAM w. ErrEL, JACK A. MccULLoUGH. 

